$\lim_{x\to0}\left(\frac{6e^x-6x-6-3x^2}{xsen\left(x\right)}\right)$

$\int\frac{x}{x^{2}+4x}dx$

$\int\frac{32x}{\left(x+2\right)\left(x-6\right)}dx$

$y'\:-\frac{2y}{x+1}=\left(x+1\right)^3$

$\frac{3}{2}\cdot\:\sqrt{\frac{4a^2}{27y^3}}$

$\sin\left(x\right)+\sin3\left(x\right)$

$\int\frac{x^5}{7}dx$